In the manufacture of refrigeration apparatus cabinets there is usually an outer shell of sheet metal and an inner liner of plastic and polyurethane insulation foamed in place between the inner liner and the outer shell. The liner includes connected walls to define a refrigerated storage space. Shelves and storage bins and the like are then selectively positioned within the storage space to provide efficient and maximum storage of articles to be refrigerated.
Within a product line of refrigerators, a manufacturer may use different styles of shelves and storage bins, as well as different configurations. Various methods of shelf installation have been used depending, in part, on whether the shelves are to be adjustable or fixed. Adjustable shelves typically employ shelf ladders fixedly secured to the liner for removably receiving shelf hooks. In a fixed shelf design, shelf supports may be fastened directly to one of the liner walls.
During the manufacturing process a liquid foam is deposited between the liner and shell. The foam expands and then hardens to fill the space. Any openings in the liner walls must be covered to prevent the liquid from escaping while it expands. The above-described shelf support systems typically achieve this by pre-installing any shelf supporting structure prior to the foaming process. Doing so requires that product differentiation be established at an early stage of manufacturing. Advantageously, a uniform cabinet design should be employed to provide economies of scale in manufacturing, with product differentiation being evident later in the assembly process. Particularly, a common cabinet design should be used from which products could be produced with shelf ladders, with several designs of shelf ladders possible, without shelf ladders, or with another method of shelf installation.
In refrigerator cabinets using shelf ladders, it is necessary to support the weight of the shelves as it is distributed from the shelf ladders to the liner. This is often done with a reinforcement bar in the foam insulation behind the liner. This requires that the reinforcement bar be installed prior to foam insulating the cabinet. It is also desirable to provide mounting points on a refrigerator liner for mounting structures besides shelf ladders, where reinforcement bars are not necessary.
The present invention is intended to solve one or more of the problems discussed above in a novel and simple manner.